stigbb



C. W. STIGER.

-CARBURETER.

APPLICATION F|LED1uLY12.1915.

Patented June 10, 1919.

cago, in the county of nn srafrns Parana* ermee.

CHARLES w. suena, or CHICAGC, ILLINoIs, AssIGNon. 'ro s 'rnoiunnne MoronnEvICnsl COMPANY, oF CHICAGO, ILLINOIS, A ConronA'rIoN or ILLINOIS.

CABBUBETEB. l

nemesi.'

To all whom t may concern Be it known that I, CHARLES W. STIGEB, a

citizen of the United States,residing at Chl- Co'ok and State ofIllinois, have invented a certain new and .useful Improvement inACarbureters, of

concise,

which the following is a full, clear, and exact description,y reference'being had to the accompanying drawings, forming a part of thisspecification.

My invention relates to carbureters for 1nlternal combustion engines,land has for its object improved means for creating and maintaining themost desirable mixture proportions for the varying demands of the enginewith which the device is connected.

In that type of carbureter wherein the I feed of gasolene 1s due toaspiration, there is a diiiiculty which is due to the fact that upon lowsuction the reduction in pressure is suliicient to lift the liquidhydrocarbon,

which is used for fuel, out of the fuel nozzle, which is provided, butis insuiiicient to take Aall of thisfuel to the engine. The result isthat ythe supply of the liquid hydrocarbon,

-such as gasolene is insuiiicient on starting and low running so faras'that which actulally goes to the engine is concerned, while, as amatter of fact, the amount of fuel really .lifted out of the nozzlewould be suiiicient.

This gasolene which is lifted out of the nozzle, but which does not getto the engine, settles on the sides of the carbure-.ting chamber'andcollects where opportunity afords, and then, when .the higher suctionsare obtained, this collected fuel goes to the engine with the regularsupply from the nozzle,

making the supply of gasolene on the higher suctions too great. This`detrimental action is commonly called loading.

My invention is concerned with means for properly vaporizing all of thegasolene which is lifted lout of the nozzle, on the low suctions, aswell as on the high suctions, and it' is 'thus calculated'l to properlyvaporize the gasolene at all suctions and to eliminate the diliicultyvwhich has been described.

` The means which I provide to carry out the above purpose, may beutilized further in supplying a desired excess of gasolene which shallbe available on starting and accelerating. These' results.v areaccomplishedbdy providii one of more assagey ways lea mgffrom ecarburetmg c amber,

porary period.

Slieccation of Letters Patent. i Pented June 109 1919. i

Application led July 12,1915. Serial No. 39,212.

Where gasolene may collect, to the interior of the VValr passagewaythrough which air enters the carbureting chamber. Since this passagewayis properly restricted, it `foltending to move the collected gasolene in'the carburetmg chamber to the interior of the air passage where it ispicked up, vaporlzed and carried on to the engine. Since the'collectionof gasolene may occur during perlods immediately receding a beginning oran increase in suction, it will be seen that any accumulation will beutilized to augment the regular flow from the nozzle at such desirabletimes and fora limited tem-l My invention .is illustrated in theaccompanym-g drawings in which- `Flgure 1 is vertical axial sectionalview of the'carbureter of my invention;

Flg. 2 is a cross sectional View taken on the plane of the line 2, 2,and looking in the direction of the arrows on Fig. 1; and

Fig. 3 is a detail view illustrating a modi.

fied form of my invention.

inlet passage-way 3, leads. A manually operated valve 3a controls thisopening. The

reference character 4, indicatesthe carbureting chamber generally, intowhich the Venturi tube extends, and from which the outlet 5 is provided,this outlet being controlled by the usual throttle valve 6. Asillustrated, the casing is provided with .the flange 7 by means of whichthe carbureter is attached to 'the engine manifold. A water jacket 8 isprovided, as shown.v

The main fuel nozzle 9 is mounted in a vertical stem 10, w-hich isformed integrally lto with a bridge 11, extending dametrically acrossthe main air inlet passage. A shelf 12 supports a float chamber 13,which communicates with-the nozzle 9 by means of 'a passage 14, and thisfloat chamber maintains a level of liquid fuel approximately on the dotand dash line w-, \being supplie through the pipe 15. f

The carbureting chamber 4 is provided -with a side extension 16 in thetop wall of which an opening 1'?l is provided. An annulus 18 is secured1n said opening, and a` npening throngh this-annulus is the auxil-vbridge-piece 19 spans this annulus. The

1ary air opening.

A hollow stem 20 is hung from a head 21,

which rests upon the ltop of the bridge-piece 19. The bottom of thisstem is provided with a collar 21', and a spiral spring 22 rests uponthis lcoll-ar. A valve 23 is provided with a hollow stem 24, which s:rounds the stem`20 and at the top of the stem 24 there is provided anadjusting cup 25', within which the spring 22 engages. It will be seennow that the valve 23 is normally held upon its seat by means of thespring 22, and that the tension ofl this spring may be varied by turningrthe cup 25, this cup being held in any adjustedvposition by a snapspring 26, which *is carried by the valve, and which lengages in any oneof a plurality of grooves 27 in the periphery of the cup. Rotation voffthe valve is prevented by the engagement vofa pin 28 ina socket 29 inthe pant 19.

The hollow stem v24 extends downwardly through an alined opening 25"11in the lower wall of this part of the carbureting chamber, and passesinto a 4dash pot 26aalined therewith, the bottom of this dash pot beinglclosed lby the cap 27a.V

A plunger 28, arranged to reciprocate in the dash pot 27a, is securedtothe bottom of the hollow stem 24 by means of a clamping screw 29,there being a clearance around the plunger. l The interior of the dashpot communicates with the passageway 14 by means of the passageway 30,which enters the dash pot justl above the plunger 28a, as shown.

A supplementaryfuel nozzle 31 is inserted.

in the hollow stem M in a position in proximity to they fuel level line,as illustrated This nozzle is fedl through the hollow stem by way of theside passageways 32. It will now be seen that gasolene can travelupwardly from lthe dash pot, through the hollow stem 24, through thenozzle 31, through the' clearance 21, around the collar 21 0n the stem20, and through the annular space in-which the spiral spring 22 isdisposed.

. A` fuel inlet port 33, which is carried on the under side of the valve23 and is directed toward rthe outlet from the canbureting chamber,communicates directly with this annular space, yas shown. A

A normally seated fuel valve 34 extends yfrom a stem 35, which isdisposed in the hollow stem 20. A spiral spring 37 surrounds the stem 35within the hollow stem 20, and

tends to keep the valve 34 seated in the nozzle 311 The stem 35 extendsupwardly beyond the head 21 and has at irts end a head 36.l

It will be seen that this is a very flexible arrangement, since the fuelvalve 34 may' thus bemade to be leither normally seated or normallyunseated. I have illustrated it as being normally seated, and it be'noted that when the valve 23 opens, the time at which fthe fuel nozzleopens will depend upon the relation of the head 36 and the opened wideras its downward movement continues.

Having thus generally described the carbureter structure in which Iembody the features ofmy invention as an instance of their employment, Ireturn now to a consideration of the Venturi tube 2 and the directlyassociated parts. It will be seen thatl the casing 1 is provided, intheform shown in Fig. 1, with an opening a forming part of' the main airpassageway. In this opening@ a ring or bushing b is closely fitted, thisring or bushing resting upon a shoulder o atthe bottom of the opening.The Venturi tube member is provided with a peripheral groove d, which isformed between a lower collar e and an upper collar f. The lower collarfits snugly within the bushing or ring b and" the upper collar in partdoes likef wise,the upper portion of the upper collar,

however, forming a shoulder g Awhich rests upon the top of the bushing:6. In this way ,the Venturi tube is definitely and firmly sup ported inposition. A plurality of apertures l1., L, extend vertically through thecollar f,

as illustrated' in Fig. 2, as well as in Fig.1,

and these apertures, as Will be seen, connect the carbureting chamberwith the peripheral groove d. By means of radial openings, i, z', the'peripheral v groove d is connected with the interior of the Venturi tube2 at its most restricted portion. It will now be seen that gasolenelifted out of the main nozzle 9 may be carried up through the Venturitube on low suctions but once in the carbureting chamber where thesuction effect is less, will ynot go to the engine, but will drop andcollect von the walls of the carbureting chamber, vultimately lfindingits way to the floor of that chamber. The pressure atthe top of theopenings h, h, is greater than the pressure at the openings z', z', dueto the restriction of the air passage and due particularly A when'aVenturi tube is employed to the rei gasolene being thus fed to theincoming air at the point of highest suction. The result is a completevaporization of the gasolene, and the potential which causes this flowis a continual one while the engine is running under circumstances whichneed correction.

In this way, the carbureting chamber is kept free from a detrimentalcollection and the consequent loading and the gasolene which is broughtdown through the open` ings h and through i is utilized to augment thegasolene from the nozzle. This condition revails on low suction, as hasbeen described, and when the throttle is suddenly opened a little extragasolene is desirable and' it will therefore be obvious how this ex` tragasolene may be furnished, due to the' condition existing immediatelypreceding lsuch acceleration. rA complete mixture is assured on lowrunning and any accumulation during a period of rest will be utilized instarting the engine.

The dash adjustment which has been described is used on starting Whereit is desired to cut down the amount of air entering the carbureter,this being done by confining the entry of air to the capacity of themain air inlet. In the starting operation the entry of air may befurther restricted by means of the valve 3 which may be closed down tolimit the entry of air to that passage through the clearancearound it,but which is wide open in subsequent running.

For a certain range of suctions, after the starting function has beenfulfilled, the

main fuel inlet and air inlet provide the proper mlxture. However, it iswell known that as the suctions are further increased,

the mixture produced by the main air and fuel inlets alone would be toorich, and,-

therefore, diluting airjor a diluting mixture is admitted from theauxiliary air inlet' or the auxiliary. air inlet and the auxiliary fuelinlet. The auxiliary air Gvalve is operated by suctions, but theinfluences whichtend to hold it upon its seat are such that it does notrespond' until after a certain degree of suction has been attained.

I refer now to Fig. 3 where it will be seen that I provide concentricnozzles instead of openings inthe Venturi tube. It will be seen that thenozzle 9 is surrounded by another nozzle k, the interior of which isconnected by means of oneI or more passageways aspiration from theinterior nozzle may be materially assisted under certain circumstancesin this Way.

I claim as new and desire to secure by Iletters Patent:

In a carbureter, a carbureting chamber, a

mixture outlet therefor, a throttle valve iny said mixture outlet, anair inlet, a Venturi tube leading from said air inlet to saidcarbureting chamber, a main fuel nozzle feeding into said Venturi tubefrom a source of supply, and a passageway leading from a point in saidcarbureting chamber below said throttle where liquid fuel may collect toan auxiliary fuel nozzle feeding into the zone of lowest pressure insaid Venturi tube,

said auxiliary nozzle being independent of the supply of fuel to saidmain fuel nozzle. In witness whereof, I hereunto subscribe my name this10th day of 'July A. D. 1915.-

- CHARLES w. sirena.,

